You can convert your money from the Borderless account page.
To convert money, select the currency that you wish to convert, and click the Convert button.
Follow the instructions on screen, where you will be prompted to enter the amount you wish to convert. You’ll be shown the fee on the same screen.
You need to make sure that you have activated the currency that you wish to convert your money to before you convert it.
Conversions usually happen within a few seconds and should be reflected in your account immediately. The conversion will be done at the mid market rate at the time that you confirmed the conversion.
There’s a cheap, transparent fee to convert between currencies (e.g. 0.35% from GBP to EUR) in your account.